Have you ever measured real water pump output flow rate?

You've probably heard me say this before, but keep the current in your
tank with the natural flow of the water. In north America this is
counterclockwise, down under (Australia) it is clockwise.

TTUL
Gary

The natural flow of water? A fish tank is too small to exhibit Coriolan
tendencies. If you are refering to something else, please explain...

"Ed Greco" wrote in message ...
The natural flow of water? A fish tank is too small to exhibit Coriolan
tendencies. If you are refering to something else, please explain...

http://www.physics.ohio-state.edu/~d...du/newcor.html :-)

The natural flow of water? A fish tank is too small to exhibit Coriolan
tendencies. If you are refering to something else, please explain...

http://www.physics.ohio-state.edu/~d...du/newcor.html :-)

I think what he is saying is that even though those forces exist, they do not exist in a
large enough scale to really effect a fish tank.

and they may or may not, I have not spent the time trying to figure it out, I do have a
125 gal grow out pond that spins "backwards" and it does so with ease so my vote as if it
mattered, is for the volume of water we have, this will not effect pump performance. if
you read the section 5.2 in your link it might explain this a little.

--
Richard Reynolds

yes, 10 feet is alot IMO, thats where all the pressure loss is going. with
psi rating, they dont rate what length that was, and psi drops with length
unless piping is RIGID, and water is HEAVY.
wolfhedd.

"nanoreef" wrote in message
le.rogers.com...
Pszemol may have written:

So I would have two questions to the group:
1. what could be the reason for so small flow rate measured?
(550-600gph expected, 339-451 measured)

The manufacturer numbers are probably based on 1.5" pipe. Quick and
dirty calculations from a fluid dynamics text book show that 10feet of
0.75" dia pipe will add about 1.7feet to the apearent height. The same
calculations for 1.5" pipe add 0.06feet (ie nothing). 1" pipe would
add about 0.5feet. That is a pretty strong argument for using 1" pipe.

cheers.

Hi Ed

Actually its Coriolis Force, named after its discoverer
Gustave-Gaspard Coriolis in 1835.

It has been proven to affect all bodies of liquid regardless of size!

Drain your sink of less than 1/2 gallon or flush your toilet of 1.6
gallons, these are much smaller than the majority of aquaria.

Ascher H. Shaprio proved the effect again in 1962 at MIT and Lloyd
Terfethen did the same at the U of Sydney in 1965.

In an aquarium, the effect may be miniscule, but it is still there
just the same. So why not keep your aquarium flowing with the natural
order of things, rather than trying to go against mother nature.

As an aside, a major contractor built a rather large fountain and did
not take into account Coriolis Force or the Curvature of the Earth.

When the fountain was filled, water did not pour over the length as
intended, but flowed only out the center. With the greater part of
the water at the apex of the counterclockwise rotation. Of course,
this was a very large fountain too.
However, the same effects would be found in even the smallest
fountain, but to such a reduced degree that it would probably not be
noticable without the most accurate test equipment.

The moon also plays a very miniscule part on our aquaria. On large
public aquaria a difference of as much as 1/2 inch can be noted
between neap tide and full tide. On a large body of water, the water
level in a large aquarium can be determined with fair accuracy using
either the Rule of Twelves or the Rule of Sevens.

TTUL
Gary

The flow rate (pressure) is always affected by the length of the pipe
regardless of pipe construction. The loss is due to friction. Pipe
construction will affect friction. However the text book makes no
distintion between any type of smooth walled pipe wether rigid or
flexible. This suggests that the difference is negligible.

or you need a better text book

mine lists several differences for

vinyl tubing smooth (assumes straight and round piece)
vinyl bubing ribbed (assumes straight and round piece)
pvc
abs

a few more though off topic of aquaria
copper
cement
galvanized
.....

even vitrified clay

--
Richard Reynolds

"Richard Reynolds" wrote in message news:6pBNb.9809$ct4.4099@lakeread05...
or you need a better text book

mine lists several differences for

vinyl tubing smooth (assumes straight and round piece)
vinyl bubing ribbed (assumes straight and round piece)
pvc
abs

So what are the differences for those?
What is the loss on 5 feet of rigid PVC compared
to stright smooth vinyl? Or to ribbed one?

So what are the differences for those?
What is the loss on 5 feet of rigid PVC compared
to stright smooth vinyl? Or to ribbed one?


shoulda known, ooh well

the tables require certain things so gona use 600gph & 3/4" and 1.5" pipe its also listed
as head loss / 100ft pipe, so you will have to figure out 5' from that.

as there are nearly 30 pages devoted to head loss in pipe so a sample of them.

material 3/4" 1.5"
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
smooth vinyl 43.3 1.5
ribbed vinyl 82 66
pvc 28.6 1
abs 30.5 1

of course the font you are using will probibly distort that table, so copy into notepad if
you want it to be a little better aligned



--
Richard Reynolds

"Richard Reynolds" wrote in message news:KyCNb.9819$ct4.7978@lakeread05...
shoulda known, ooh well

the tables require certain things so gona use 600gph & 3/4" and 1.5" pipe its also listed
as head loss / 100ft pipe, so you will have to figure out 5' from that.

as there are nearly 30 pages devoted to head loss in pipe so a sample of them.

material 3/4" 1.5"
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
smooth vinyl 43.3 1.5
ribbed vinyl 82 66
pvc 28.6 1
abs 30.5 1

Thank you. I know many people using ribbed vinyl pool hose for their
overflow boxes drainage... I see that smooth vinyl is much better.

Do you have in this table values for 1" as well?

of course the font you are using will probibly distort that table,
so copy into notepad if you want it to be a little better aligned

No, everything is fine. I learned long time ago newsgroups need to be
read with something like courier or any other not-proportional font
to reflect ASCII-arts or tables made up with ASCII characters...

Thank you. I know many people using ribbed vinyl pool hose for their
overflow boxes drainage... I see that smooth vinyl is much better.

yea

Do you have in this table values for 1" as well?

from 1/4" to 3" in 1/4" incriments

material 1"
-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
smooth vinyl 15
ribbed vinyl 74.4
pvc 7.1
abs 7.1


of course the font you are using will probibly distort that table,
so copy into notepad if you want it to be a little better aligned

No, everything is fine. I learned long time ago newsgroups need to be
read with something like courier or any other not-proportional font
to reflect ASCII-arts or tables made up with ASCII characters...

i figured you might, but didnt know who else would be checking it out.


--
Richard Reynolds